This invention relates to a rolling bearing device used for a wheel supporting structure of a vehicle.
There is a previously known wheel supporting device in a vehicle in a structure having a drive shaft rotating integrally with a wheel, the drive shaft connected with a hub for mounting the wheel and the hub rotatably supported by a knuckle through a bearing (see JP-A-2000-71710).
Further, in the bearing used in such a wheel supporting device, muddy water will invade between its inner ring and outer ring. Thus, there is a known bearing device which prevents invasion of the muddy water by a sealing device provided between the inner and outer rings (see JP-A-2006-208038).
However, in this bearing supporting device, as shown in FIG. 10, the muddy water will invade the sealing device C1 side of a bearing C from the clearance D located between an outer peripheral surface A1 of a drive shaft A and a mounting opening B1 for inserting the bearing C in a knuckle B. During traveling, the muddy water will vigorously invade the sealing device C1 side so that as the case may be, with only this sealing device C1, invasion of the muddy water cannot be prevented. In order to prevent such invasion of the muddy water, it is known that a deflector E having a labyrinth function is provided between the outer peripheral surface A1 of the drive shaft A and the mounting opening B1 of the knuckle B. In this structure, in order to press-fit the deflector E onto the outer peripheral surface A1 of the drive shaft A, the outer peripheral surface A1 must be subjected to cutting. On the other hand, as to the inner peripheral surface B2 of the mounting opening B1 of the knuckle B, a clearance F has to be formed to give the labyrinth function between the inner peripheral surface B2 and the outer side E1 of the deflector E so that the inner peripheral surface B2 has to be also subjected to cutting. In addition, these cuttings require gauging process owing to changes in the tolerances of the respective components.